Leviticus 18:19 in the King James Version
Also thou shalt not approach unto a woman to uncover her nakedness, as long as she is put apart for her uncleanness.
Context
18 “‘You shall not take a wife in addition to her sister, to be a rival, to uncover her nakedness, while her sister is still alive.
19 “‘You shall not approach a woman to uncover her nakedness, as long as she is impure by her uncleanness.
20 “‘You shall not lie carnally with your neighbor’s wife, and defile yourself with her.